1. Field of the Invention
The present invention relates to an image recording method and apparatus and a recording medium, and in particular to a technique of managing parameters used for image processing during image recording on a recording medium based on image data.
2. Description of the Related Art
An inkjet printer, which is a form of an image recording apparatus, includes a recording head provided with a plurality of ink ejection ports (nozzles), and records an image on a recording medium by controlling an operation of ejecting ink from each of nozzles on the basis of image data as a print object. Each of the nozzles on the recording head varies in recording characteristics (ink ejection characteristics). If an image is formed without addressing the variation, various head characteristics, such as variation in the amount of ejected ink, variation in ink deposition position, and variation in ink concentration between the nozzles, are affected, thereby causing concentration unevenness in an image of a printed matter.
Accordingly, in general, a conventional inkjet printer includes a processing system (concentration unevenness correcting process system) for correcting concentration unevenness to prevent concentration unevenness from occurring. Use of this concentration unevenness correcting process system generates a concentration unevenness correction parameter, which is a concentration unevenness correction value, and performs an image data converting process to which the concentration unevenness correction parameter is applied.
As techniques of correcting concentration unevenness, various methods have been proposed, including, for instance, a method described in Japanese Patent Application Laid-Open No. 2010-082989. An overview of the technique of correcting concentration unevenness disclosed in Japanese Patent Application Laid-Open No. 2010-082989 is as follows. First, a test chart for measuring concentration for acquiring a concentration converting function for correcting concentration unevenness is output. An image of the output test chart for measuring concentration is read. A recorded concentration is measured. A signal converting function (concentration converting function) for image data is generated for each nozzle on the basis of the measured concentration data. When an image is printed, input image data is corrected on the basis of the concentration converting function, and image recording is controlled on the basis of the corrected image data, thereby forming an image where concentration unevenness is prevented from occurring.